1231117281631 has 2 divisors, whose sum is σ = 1231117281632. Its totient is φ = 1231117281630.

The previous prime is 1231117281593. The next prime is 1231117281643. The reversal of 1231117281631 is 1361827111321.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1231117281631 - 2¹³ = 1231117273439 is a prime.

It is a super-2 number, since 2×1231117281631² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1231117281431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615558640815 + 615558640816.

It is an arithmetic number, because the mean of its divisors is an integer number (615558640816).

Almost surely, 2^{1231117281631} is an apocalyptic number.

1231117281631 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231117281631 is an equidigital number, since it uses as much as digits as its factorization.

1231117281631 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12096, while the sum is 37.

The spelling of 1231117281631 in words is "one trillion, two hundred thirty-one billion, one hundred seventeen million, two hundred eighty-one thousand, six hundred thirty-one".